Neurotransmitters Lec 7 Flashcards
Iontoropic NT receptors
Ligand-gated ion channels
4-5 subunits that each contain 3 or 4 transmembrane domains
Metabotropic NT receptors
G-protein-couple receptors
Monomeric proteins containing 7 transmembrane domains
Acetylcholine
PNS-NMJ
CNS-interneurons in brainstem/forebrain- involved in AD
ACh precursor
Acetyl CoA and Choline
ACh removal
Acetylcholinesterase
ACh organophosphates- insecticides and sarin
inhibit Acetylcholinesterase
ACh receptors
Ionotropic/nicotinic- excitatory
Metabotropic/muscarinic- brain and peripheral ganglia
- mediate responses of autonomic effector organs
ACh useful therapeutics
Atropine- antagonists- pupil dilation
Scopolamine- motion sickness
Myasthenia Gravis
Autoimmune Dz- against nAchR
increased turnover of receptors
muscle fatigue
Glutamate
Excitatory in brain
Excitotoxcity
High EC concentrations toxic to neurons
Glu precursor
Glutamine
Glu removal
Reuptake into terminal and glia
Glu receptors
Ionotropic- NMDA, AMPA, Kainite
Metabotropic- increase or decrease excitability of postsynaptic cell
GABA
Major inhibitory transmitter in CNS
GABA precursor
Glutamate
GABA removal
Reuptake into terminal and glia
Decreased GABA
can cause epilepsy
GABA receptors
Ionotropic- GABAa and GABAc
- open inhibitory Cl channels
- Benzodazepines and barbiturates
Metabotropic- GABAb
- in Brain
- produces inhibitory postsynaptic response
Glycine
Spinal cord
inhibitory
Gly precursor
Serine
Gly removal
Reuptake into terminal and glia